The Fax Service Provider ‘Microsoft Modem Device Provider’ encountered a problem and needed to close.
Error Code: 0xC0000005
This error code indicates the cause of the error.
A Windows Error Report was generated with full details about the problem.
The Fax service will restart now.

I knew that our hardware was fine as the modem was an external US Robotics Serial modem that had just come off another server.

Fixing the crashing Windows Server 2012 r2 Fax Server

I am sure Microsoft will come out with a proper fix for this problem, but in the meantime this work around will have to do!

The problem is caused by the fxst30.dll file which is located in c:\windows\system32. We can replace that DLL with a DLL from a Windows 7 installation and then it works fine.

First of all, shut down the fax service so that the DLL is not in use. The service is simply called “Fax”.

Navigate to c:\windows\system32 on the server with the problem and find the fxst30.dll file. Right click on the file and choose properties. Go to the security tab and then click on advanced. Click on the “Change” button next to the owner and change the owner from “TrustedInstaller” to the administrator account you are using to make these changes.

Back in Windows explorer rename the file to “FXST30-original.dll”.

Copy FXST30.dll from a Windows 7 machine into the system32 folder of your server. This is what the two versions of the file I had looked like (Windows Server 2012 r2 on right):

The file that ships with Windows Server does seem to be more recent than the one that comes with Windows 7 – but apparently does not work very well!

Start the Fax Service up again and hopefully you should be able to receive faxes on Windows Server 2012 r2!

Define the “Logon as a Service” policy and add the user “domain\ServerAdmin$”. It should look like this:

You may need to wait a while or force or group policy update before trying the Windows Server Essentials r2 configuration wizard again. But as long as you have set this correctly it should move on to the next stage normally: